Dependence of the current coefficient of frequency modulation of single-mode semiconductor lasers on the constant injection current and on the frequency of the modulating signal

An analysis is made of typical dependences of the current coefficient of frequency modulation of single-frequency homojunction lasers on the modulation frequency f_m and on the constant injection current. In the case of fast modulation characterized by f_m > 1 MHz the different nature of these dependences is interpreted by assuming that the nonequilibrium electron temperature differs from the crystal lattice temperature.